Improvement in sheet-metal keys for locks



PATENT GEEIOE.

'rirus rOwERs, OE NEW YORK, N. Y.-

IMPROVEMENT IN SHEET-METAL KEYS FOR LOCKS.

Specification forming part of Letters Patent No. 117,110, dated July 18, 1871.

To all whom t may concern:

Be it known that I, TITUs POwERs, of the city, county, and State of N ew York, have invented a new and Improved Lock-Key, of which the following is a. specification, reference being the key it is desired to make.

had toL the accompanying drawing forming part of the same.

Figures l and 2 are halves of my key, intending to show a method by which the saine may be made. Fig. 3 is an edge view of a section of vthe said halves cut through on the dotted linea' w; Fig. 4, a completed key as made with a round shank from the halves, Figs. l and 2.

f My invention relates to a hollow lock-key as a t new article of manufacture fabricated from sheet metal, the outline of its internal cavity bein g made to conform in shape to its external contour, thereby securingequal strength as in a solid key,

while a saving both in metal and cost of fabricaing one-half of a hollow shaft or tube. Then place these halves together and unite them by soldering' or brazing. I/Vhen thus completed they forni the key, Fig. 4.

By this method a key may be made at a small cost, and a considerable saving of material is effected without loss of strength, while the key, being made lighter than if solid, is more conveniently and pleasantly carried.

The method of forming tubes for various purposes in halves and then uniting the halves by soldering or brazing being' in use, I do not claim such method, of itself, of making tubes. I am also aware that the stems of keys vhave been made hollow by drilling a straight hole or cavity through them, as will be found described in the English patents of R. Larkin of 1854, and Hamilton & Nash of 1859. I do not, therefore, claim, broadly, a key having a hollow stem 5 but What I do claim, and desire to secure by Letters Patent, is-

A hollow lock-key fabricated from sheet metal, when the Outline of the internal cavity conforms in shape to' the external contour of the key, as set forth.

Witnesses:

J OEN J. CARROLL, JAMEs HAGAN.

TITUS POWERS. 

